Calibration device for electric meter including a control magnet mounted on a flexible arm

Claim 2

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said controL magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a flexible arm of nonferrous material mounted on said meter and spaced from said movement magnet, said control magnet being pivotally attached to a biased end of said arm, said biased end of said arm being movable relative to said movement magnet, and a screw adjustment means bearing upon said flexible arm for adjusting the distance between said biased end of said flexible arm and said movement magnet and thus adjusting the sensitivity of said meter.

Claim 3

The electrical meter recited in claim 1 further including: a movement bracket fixedly mounted in said meter, said movement bracket being U-shaped and having bearing seats in two arms thereof, said movement assembly being pivoted in said bearing seats, said flexible arm being affixed at one end thereof to said movement bracket, the other end of said flexible arm being movable to adjust the distance between said control magnet and said movement magnet.

Claim 4

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a flexible arm of non-ferrous material, said control magnet being pivotally attached to said arm, said arm being movable to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, a movement bracket fixedly mounted in said meter, said movement bracket being U-shaped and having bearing seats in two arms thereof, said movement assembly being pivoted in said bearing seats, said flexible arm being affixed at one end thereof to said movement bracket, the other end of said flexible arm being movable to adjust the distance between said control magnet and said movement magnet, and an adjusting screw, said flexible arm having a threaded opening such that said adjusting screw may be threaded therein to bear against said movement bracket to adjust the distance between said control magnet and said movement magnet.

Claim 5

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a flexible arm of non-ferrous material, said control magnet being pivotally attached to said arm, said arm being movable to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, a movement bracket fixedly mounted in said meter, said movement bracket being U-shaped and having bearing seats in two arms thereof, said movement assembly being pivoted in said bearing seats, said flexible arm being affixed at one end thereof to said movement bracket, the other end of said flexible arm being movable to adjust the distance between said control magnet and said movement magnet, and an adjusting screw, said flexible arm having a threaded opening such that said adjusting screw may be threaded therein to bear against said movement bracket to adjust the distance between said control magnet and said movement magnet.

Claim 6

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a movement bracket fixedly mounted in said meter, said movement bracket being substantially U-shaped and having bearing seats in two arms thereof, said movement assembly being pivoted in said bearing seats, a flexible arm of non-ferrous material, said control magnet being pivotally attached to said arm, said arm being affixed to said movement bracket, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet, an adjusting screw, said movement bracket having a threaded opening therein and said flexible arm having an opening therein for receiving said adjusting screw, said adjusting screw being positioned in said opening in said flexible arm and threaded into said threaded opening in said bracket so that said adjusting screw can be turned to adjust the distance between said control magnet and said movement magnet.

Claim 7

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a movement bracket fixedly mounted in said meter, said movement bracket being substantially U-shaped and having bearing seats in two arms thereof, said movement assembly being pivoted in said bearing seats, a flexible arm of non-ferrous material, said control magnet being pivotally attached to said arm, said arm being affixed to said movement bracket, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet, an adjusting screw, said movement bracket having a threaded opening therein and said flexible arm having an opening therein for receiving said adjusting screw, said adjusting screw being positioned in said opening in said flexible arm and threaded into said threaded opening in said bracket so that said adjusting screw can be turned to adjust the distance between said control magnet and said movement magnet.

Claim 8

The meter recited in claim 4 further including: a coil spring positioned on said adjusting screw between said movement bracket and said flexible arm to provide bias so that said flexible arm will move in both directions in response to turning of said adjusting screw.

Claim 9

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a flexible, substantially L-shaped arm of non-ferrous material mounted on said meter and spaced from said movement magnet, said control magnet being pivotally attached to one end of said arm, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, wherein said arm has a short leg and a longer leg, said short leg having a threaded opening, and an adjusting screw received by said threaded opening so that said adjusting screw bears against said longer leg to adjust the distance between said control magnet and said movement magnet.

Claim 10

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a flexible, substantially L-shaped arm of non-ferrous material mounted on said meter and spaced from said movement magnet, said control magnet being pivotally attached to one end of said arm, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, wherein said arm has a short leg and a longer leg, said short leg having a threaded opening, and an adjusting screw received by said threaded opening so that said adjusting screw bears against said longer leg to adjust the distance between said control magnet and said movement magnet.

Claim 11

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a movement bracket for supporting said movement assembly, and a flexible, substantially L-shaped arm of non-ferrous material affixed to said movement bracket, said control magnet being pivotally attached to one end of said arm, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, wherein said arm has a short leg and a longer leg, said longer leg having a cut-out tongue portion therein, said cut-out tongue portion being adjustable to bear against said movement bracket to adjust the distance between said control magnet and said movement magnet.

Claim 12

An electrical meter comprising: a pivoted movement assembly including at least one movement magnet, a scale, a pointer mounted on said movement assembly and positioned for movement over said scale, a coil producing magnetic flux which interacts with said movement magnet to move said pointer over said scale in response to current through said coil, a control magnet pivotally mounted for rotation relative to said movement magnet for adjustment of the zero position of said pointer relative to said scale, the interaction between said control magnet and said movement magnet acting to restore said pointer to said zero position when said current through said coil is reduced, a movement bracket for supporting said movement assembly, and a flexible, substantially L-shaped arm of non-ferrous material affixed to said movement bracket, said control magnet being pivotally attached to one end of said arm, said arm being movable relative to said movement magnet to adjust the distance between said control magnet and said movement magnet to adjust the sensitivity of said meter, wherein said arm has a short leg and a longer leg, said longer leg having a cut-out tongue portion therein, said cut-out tongue portion being adjustable to bear against said movement bracket to adjust the distance between said control magnet and said movement magnet.